While heterogeneous network significantly improve system performance, they also face some problem to be solved, especially downlink (DL) control channel interference in co-channel deployment. As most of control channels (CCH), e.g. physical broadcast channel (PBCH), physical downlink control channel (PDCCH), physical control format indicator channel (PCFICH) and physical HARQ indicator channel (PHICH) are transmitted at the fixed location in signal frames and can not be scheduled to other resource blocks, thus interference to control channels will be caused when co-channel deployment is adopted by cells neighboring to each other, particularly a Macro cell and a neighboring small cell, for example the cell of a relay node, a Pico base station, or a Femto base station. In co-channel deployment, a radio link of a UE is apt to fail under harsh interference conditions.